Sanitary tampon

ABSTRACT

An absorbent material and method of constructing such material is disclosed. The absorbent material includes at least two united constituents, one of which contains filaments with a portion of such filaments transferred through openings in the other constituent. The transference may be effected through the use of transfer needles, which not only transfers filaments but additionally provides the openings through which the filaments extend. The absorbent material is particularly adapted for use in a tampon or other other catamenial device. Other uses, such as in disposable diapers or in other products where a relatively high degree of absorbency in a relatively economical product is desirable are also contemplated.

Unite Dostal States Patent 1451 Oct. 3, 1972 [54] SANITARY TAMPON [72]Inventor: Zdenek Denny Dostal, Dover, Del.

[73] Assignee: International Playtex Corporation,

New York, NY.

[22] Filed: Jan. 22, 1970 [21] Appl. No.: 5,080

[52] US. Cl. ..128/285, 19/1445, 28/72.2 R, 161/159, 264/273 [51] Int.Cl. ..A6lf 13/20 [58] Field of Search ..128/156, 284, 287, 290, 296;19/1445, 145; 161/80, 159; 264/271, 273;

[56] References Cited UNITED STATES PATENTS 461,602 10/1891 Boult ..28/4N 3,085,309 4/1963 Olson ..128/284 x 3,122,140 2/1964 Crowe, Jr...128/156 x 3,431,909 3/1969 Krusko ..128/285 3,451,885 6/1969 Klein..161/80 3,482,570 12/1969 Schuster 128/ 1 56 4/1970 Crosby ..28/72.2 R12/1970 Wicker et a1. ..128/156 Primary Examiner-Charles F. RosenbaumAttorney-Jeffrey A. Schwab and Stewart J. Fried ABSTRACT An absorbentmaterial and method of constructing such material is disclosed. Theabsorbent material includes at least two united constituents, one ofwhich contains filaments with a portion of such filaments transferredthrough openings in the other constituent.

The transference may be effected through the use of transfer needles,which not only transfers filaments but additionally provides theopenings through which the filaments extend.

The absorbent material is particularly adapted for use in a tampon orother other catamenial device. Other uses, such as in disposable diapersor in other products where a relatively high degree of absorbency in arelatively economical product is desirable are also contemplated.

3 Claims, 13 Drawing Figures PATENTEDnma I972 v 3.695.270 sum 1 or 3 Ymix-70R] I0 ZDENEK DENNY 005m.

BY Muir S Fm L ATTORNEY PATENTEDncra m2 3,695,270

' sum 2 or 3 "LWEXTOR. ZDENEK DENNY DOSTAL y fllubmu' S E w i & 5% QDQPATENTEDUCT 3 m2 SHEET 3 [1F 3 INVPINIOFL ZDENEK DENNY DOSTAL SANITARYTAMPON The present invention relates to an absorbent material and themethods of making the same. While variousapplications for such absorbentmaterial are contemplated, the present invention finds specificapplication for use in catamenial devices such as tampons.

Tampons enjoy a wide acceptance and various catamenial devices have beendeveloped, employing various material compositions which must provide arelatively high degree of absorbency in a product which is relativelycompact and economical to manufacture.

Aside from its absorbent characteristics, the material employed must becomfortable so as to allowready insertion into the vaginal canal; have astrength sufficient to retain its' integrity in use; and further havethe ability to expand once subjected to the moisture in the vaginalcanal so as to conform to the space between the walls of the canal toprevent leakage of the menstrual discharge and still allow for easywithdrawal.

The materials employed must also be adapted to be made economically bothwith respect to material cost and manufacture processes.

Present catamenial devices generally employ fibrous materials such ascellulosic structures, principally rayon, cotton, paper or mixtures orblends thereof depending principally upon the absorptive capacities ofthe bulk of the materials to increase absorbency. Aside from varying thetype of raw materials employed, by and large developments to increaseand/or enhance absorptive capacity has been dealt with by either addingto the bulk of the material and/or the compression of the materials soas to add quantitatively to the mass of absorbent material within agiven volume.

As hereinafter more specifically described, a method has been found toincrease the absorbency levels of more economical, lesser absorbent rawmaterials so as to enable the substitution of such materials, in, forexample a catamenial device, with the finished product having anabsorptive capacity which is at least at a parity with a product ofequal weight heretofore constructed of more expensive, greater absorbentraw materials.

According to the present invention it has been found that absorptivecapacity is increased through the use in a tampon of an absorptivematerial having at least two layers where at least one of the layers hasabsorptive capabilities and at least one of the layers includesfilaments, wherein a portion of the filament of the filament bearinglayer has been transferred completely through openings in the othercompanion layer.

It has been determined that particularly desirable results are obtainedif the two layers are dissimilar and where both layers are absorbentmaterials. Further, one of the layers preferably is adapted to act as amatrix with the filaments of the otherof the layers extending throughopenings in the matrix layer.

For example, a tampon having absorbent material weighing 2.2 grams, 50percent of which is rayon and 50 percent of which is cellulose crepewadding normally has an absorbency equal to only 80 percent of anidentically constructed, more expensive all rayon tampon havingabsorbent material weighing 2.2 grams.

If however, the same rayon and cellulose crepe wadding constituents aremodified in accordance with the present invention to provide openingsthrough the cellulose crepe wadding, and a plurality of the filaments ofthe rayon are transferred through such openings the tampon will have anabsorbency level equal to the more expensive all rayon tampon.

The absorptive composite of the present invention is preferably formedby juxtaposing in substantially superimposed relationship, twoconstituent materials; at least one of such materials being of anabsorptive substance, and at least one of such materials includingfilaments; forming openings through at least one of such materials, andtransferring filaments from such filament bearing material through theother of such materials.

Preferably the formation of the openings and the filament transferencesteps are accomplished in a single operation by the use of barbedneedles, such as the type commonly referred to as felting needles with aleast portion of the barbs oriented along the shank of the needle in thedirection of the desired filament transference.

In a tampon it is preferably that the transference of filaments be of adegree such that the number of filaments on either face of the matrixlayer be substantially equal.

It is believed that the increase in absorbency of the material of thepresent invention is due to alteration in the interstitial spacingeffected during transference, the increase of the surface area effectedin the creation of the openings, and/or the wicking or capillaritybetween layers along the transferred through filaments. The transferredthrough filaments act not only to maintain the integrity of the unitedconstituent materials but further serve to maintain the integrity of theopenings through the layers. This latter feature has special pertinencyin the use of the absorbent material in catamenial devices where theforming machinery generally exerts a crimping pressure on the materialbeing processed to shape and set the tampon.

Although such novel feature or features believed to be characteristic ofthe invention are pointed out in the claims, the invention and themanner in which it may be carried out may be further understood byreference to the description following and the accompanying drawings.

FIG. 1 is a top elevational view of an absorbent material of the presentinvention, with a corner of one of the layers folded back to indicatethe manner in which the filaments of one layer are transferred throughthe openings provided in the. other layer.

FIG. 2 is a cross sectional view taken along lines 22 of FIG. 1 withdimensions exaggerated for clarity.

FIG. 3 is a cross sectional view, also exaggerated for clarity, ofanother embodiment of the present invention.

FIG. 4 is a cross sectional view, similarly exaggerated for clarity, ofan alternate embodiment of an absorbent material of the presentinvention.

FIG. 5 is a schematic illustration of an apparatus for constructing anabsorbent material in accordance with a method of the present invention.

FIGS. 6a-c are side elevations illustrating the sequential filamenttransference of the present invention; FIG. 6a illustrating superimposedlayers of constituent material before the entry of the transfer needle;FIG. 6b illustrating a transfer needle as it transfers filaments; andFIG. 6c illustrating the transfer needle as it is withdrawn from theunited constituent layers with the transferred filaments extendingthrough the openings.

FIGS. 7-9 are side elevational views of various transferring needleswhich may be employed.

FIG. 10 is a sectionalized perspective of a portion of a tamponemploying absorbent material of the present invention.

FIG. 11 is a side elevation illustrating the absorbent material of thepresent invention formed as a tampon and disposed within a tamponinsertion device, partially cut-away.

Referring now to the figures in greater detail, where like referencenumbers denote like parts in the various figures.

Illustrated in FIGS. 1 and 2 is one form of an absorbent composite l ofthe present invention. While various materials may be employed, theparticular composite shown comprises two dissimilar constituents 2,3,both of which are absorbent, and at least one of which (2) containsrelatively long filaments. For example, one of the constituents 2 is afibrous substance, such as rayon and its companion constituent 3 is anabsorbent paper such as cellulose crepe wadding.

As shown in FIGS. 1 and 2 the absorbent composite is provided with aplurality of openings 4 extending through the cellulose crepe waddinglayer 3 through which the filaments 2' of the rayon fibrous material 2pass, such that filaments 2' and 2" extend on opposite faces of thecrepe wadding layer 3.

For clarity, the constituents 2,3 may be referred to as layers althoughas illustrated in FIGS. 1 and 2, the transference of the fiber filaments2 of the fibrous material 2 through the companion layer 3 has beenaccomplished in a manner so as to substantially equalize the number oftransferred filaments 2' and non-transferred filaments 2" at the opposedfaces of the companion layer 3.

In FIG. 3 the absorbent composite 5 illustrated also includes dissimilarconstituents with a fibrous layer 6 and a companion matrix layer 7.However, a lesser portion 8 of the filaments of the fibrous layer 6 aretransferred through the openings 9 in the companion matrix layer 7 so asto be exposed on the outer face of the companion layer 7. 7

Whereas FIGS. 1-3 illustrate embodiments including two starting layers,various other combinations of multi-layers of material are possible. InFIG. 4 for example there is illustrated an absorbent composite 10including an inner layer of fibrous material 11 and a pair of outermatrix layers 14. A portion of the filaments 12 of the inner layer 11have been transferred through openings 13in both outer superimposedlayers 14.

It is to be appreciated that the layers bf the absorbent compositeillustrated in FIGS. 1-4 are not necessarily as clearly defined asillustrated. In the=manufacture of such material the filamenttransference is such that while the constituent materials retain theirrespective identities a selective union of the materials resultsvisually integrating the constituents.

The amount of openings and filaments transferred per unit, can varydepending upon the degree of increased absorbency desired ranging from asmall number of openings to that degree of openings which would destroythe matrix layer. Since it is desired to have at least some filamentspassing through each of the openings to maintain the integrity of theopenings, a particularly favorable union would be a uniting such asillustrated in FIG. 2 where there is a substantial equalization offilaments on opposite faces of the matrix layer. There is thus providedsubstantially equalized wicking on both faces of the matrix withfilaments extending through all of the openings.

Referring to FIG. 5 there is illustrated an apparatus for processing anabsorbent composite in accordance with the present invention.

A web of fibrous material 15 is fed such as from a spool 16 to a needlepunching machine 17. A second web of material 18 is also fed, such asfrom a spool 19 so as to lie in superimposed relationship with thefibrous material 15 when the two webs 15,18 are positioned at the workstation area 20 of the needle punching machine 17.

The needle punching machine 17 depicted is but a schematicrepresentation encompassing in a broad sense the basic operation ofneedle punch equipment, it being understood that various apparatus areavailable to perform the fiber filament transference and hole punchingfunctions requisite in forming the absorbent material of the presentinvention. As illustrated, the needle punching machine 17 includes anreciprocally driven piston 21 adapted to drive a needle beam 22 carryinga plurality of vertically oriented barbed needles 23 so as to verticallyactuate the needles 23 to vertically reciprocate them into needlereceptacles 24 in the bed 25. A transference of the filaments and aunion of the webs 15, 18 also occurs and the so processed resultantabsorbent material 27 is taken up,such as by take-up spool 28.

As is more clearly illustrated in FIGS. 6a-c, the needles 23 passthrough the webs 15,18 effecting openings. The barbs 26 effect a fiberfilament transference from the'fibrous web 15 through the formedopenings in the second web 18.

The orientation of the barbs and the stroke of the needles must be suchas to effect a transference, that is the barbs must pass completelythrough the webs. The sequential steps are illustrated in FIGS. 6athrough 6c wherein the barbs 26 engage a portion of the filaments on theweb 15. The point of the needle 23 punctures the web 18 and thefilaments engaged by the barbs 26 are transferred through the openingsso made. The needle 23 is then retracted with the filaments disengagedfrom the barbs, such filaments remaining within the openings andextending through the web 18.

Various needle configurations are possible. In FIG. 7 for example theneedle 29 is constructed having barbs 30 disposed along its shank 31such that the barbs 30 would engage filaments and transfer them in thedirection of the arrow A. Such a needle configuration would be employedwhere the shank 31 would first pass through the fibrous material andthen the transferee web such as is shownin FIG. 5 and FIGS. 6a-c.

Were the web superimposition of FIG. 5 reversed, such as by having thetransferee web first subjected to the needle shank, a needle 32 such asillustrated in FIG. 8 would be suitable. The barbs 33 on the needle 32are aligned so as to engage a portion of the fiber filaments on thefibrous 'web and draw such filaments through the needle made openings inthe transferee web. Or, in the alternative in lieu of the unidirectionalfiber filaments transference of FIG. 5, transference between webs can beaccomplished from both above and below the webs employing variouscombinations of needles 29,32 and 34 illustrated in FIGS. 7,8 and 9respectively.

Further this multi-station, above and below technique may be employed,where multiple webs are employed, such as the three webs which initiatethe absorbent material 10 shown in FIG. 4.

An alternative method of constructing a multilayered composite such asthe composite of FIG. 4 may be accomplished by use of needles, such asillustrated by the needle 34 of FIG. 9. The needle 34 of FIG. 9 includesalong its shank 31, both barbs 36 for transference in one direction andbarbs 37 for transference in the opposite direction. The downward strokeof the needle through the multiple webs would transfer filaments in thedirection of the stroke through the bottom web. The reciprocalretracting motion of the needle would transfer filaments from thecentral web of fibrous material through the upper web.

Filament transference including the provision of openings has resultedin increased absorbency and this has been found to be of particularvalue in the construction of tampons. As illustrated in FIG. 10, atypical tampon structure of the present invention is shown.

The tampon illustrated may be constructed in a variety of ways usingvarious manufacturing techniques. For example, a multiphase linear flowmachine such as depicted in US. Pat. No. 3,465,390 to Mooney may beemployed.

The tampon 43 shown includes two layers of superimposed absorbentmaterial 38 constructed in accordance with the present invention. Agauze layer 44 for strong securement is positioned between the twoabsorbent material layers 38 and a withdrawal string 39 extends throughthe layers 38, 44.

While a gauze layer 44 has been illustrated such gauze layer 44 may bedispensed with in embodiments where the matrix layer of the absorbentmaterial 38 is of a sufficient strength to maintain the string 39securely even after the absorbent material 38 has been subjected tomoisture. I

Illustrated in FIG. 1 1 is the tampon of FIG. 10 loaded into atelescoping tube inserter device 40 such as. those presently availablein the art. It might further benoted that as formed the openings 41 andfibers 42 extend transversely with respect to the body portion of thetampon thus facilitating not only the absorption of menstrual fluid, butfurther present a network of openings for the menstrual discharge.

As will be seen from the examples which follow, combined absorbent andnon-absorbent materials can be employed in the formation of anacceptable starting material for use as a tampon and the non-absorbentconstituents may be chosen for both strength and selectivefunctionality. Further, enhancement of absorbent characteristics is alsoprovided in an all rayon combination.

The following test results are believed indicative of the enhancedproperties of an absorbent material constructed in accordance with thepresent invention.

So as to provide more definitive results all of the following sampleswere formed into tampons and absorbency levels were determined in suchcondition. Each of the tampons tested had a weight of approximately 2.4grams with 2.2 grams being of absorbent material and the remaining .2grams including the intermediate gauze layer. It is of note that in themaking of the tampons pressure is applied to the material surface toclose some of the openings in those samples (such as samples V and VIinfra, where the shortness of the filaments of the cellulose crepewadding prevented such filaments from maintaining the integrity of theopenings, thus accounting in some degree for the relatively minorincrement in absorbency levels.

Absorbency levels were tested employing the Syngyna Method. A summary ofthe Syngyna Method may be found in a paper entitled A Comparison of theAbsorptive Efficiency of the Commercial Catamenial Tampons" written byProfessor G.W. Rapp and published in June 1958 (Dept. of Research,Loyola Univ., Chicago, Ill.)

The Syngyna Method basically consists of applying to a properlypositioned tampon an adaptation pressure of physiological magnitude andthen allowing a fluid of proper consistency to flow at its tip at acontrolled rate. The test is concluded when the first drop of fluidbegins to fall from the open end of the Syngyna regardless of whetherthe tampon seems saturated or not.

Using as a control an all rayon tampon [weighing 2.4 grams] which has aSyngyna absorbency level in grams of l 1.2, the following tests areexemplary of the present invention. The examples are given by way ofillustration and are not intended to limit the invention.

Material Transference Employed Method Results 50% rayon 3 Barbedneedles, Syngyna absorbency denier, 1 9/16 triangular shank, of 11.2grams fiber length 15 gauge (0.072 50% cellulose inch) diameter crepewadding 800 needle holes 10 lb. per 3,000 per square inch sq. feet (l0 9barbs per plies) needle Material Transference Employed Method Results50% rayon 3 NONE Syngyna absorbency denier, 1 9/16 of 9.0 grams fiberlength 50% cellulose crepe wadding 10 lb. wgt. per 3,000 sq. feet (10plies) The 50 percent rayon, 50 percent cellulose crepe wadding sampleexhibited progressively enhanced absorbency levels as the needletransferring operation progressed as can be seen from the chart below:

SYNGYNA ABSORBENCIES IN GRAMS NO 400 800 Punches Punches Punches PunchesControl A further desirable result of the above two samples wasdiscovered. A single layer of cellulose crepe wadding (10lb. wgt. per3,000 sq. feet l ply) alone was needle punched by the same needlepunching equipment of sample I. Such sampling started to loose itsintegrity at approximately 800 punches per square inch whereas the samematerial maintained its integrity when subjected to the same amount ofneedle punches as part of the rayon-cellulose crepe wadding union ofsample I. y As can be noted from sample I above a more economicalmaterial, that is cellulose crepe wadding has been substituted for asubstantial portion of the rayon in the tampon. Normally, as shown in'sample II this substitution would effect a 20 percent loss inabsorbency. However, as illustrated the material of sample I was broughtto the level of absorbency of an all rayon tampon of equal weight.

III

Material Transference Employed Method Results 40% rayon 3 Barbedneedles, Syngyna absorbency denier, l 9/l6 triangular shank, of 10.40grams fiber length 15 gauge (0.072 60% cellulose inch diameter) crepewadding 800 needle holes lbv wgt. per per square inch 3,000 sq. feet 9barbs per needle l0 plies) Material Transference Employed Method Results25% rayon 3 Barbed needles, Syngyna absorbency denier, l 9/ l6triangular shank. of 9.30 grams fiber length gauge (0.072 75% celluloseinch) diameter crepe wadding 800 needle holes lOIb. wgt. per per squareinch 3000 sq. feet 9 barbs per needle l0 plies) Material TransferenceEmployed Method Results 100 cellulose Barbed needles Syngyna absorbencycrepe wadding triangular shank, of 8.8 grams 10 lb. wgt. per 15 gauge(0.072 3,000 sq. feet inch) diameter l0 plies) 800 needle holes persquare inch 9 barbs per needle It should be noted that a 100 percentcellulose crepe sampling constituted of exactly the same materials ofsample V. but not subjected to the needle punching has a Syngynaabsorbency of 8.6 grams. It is of interest to note that the fibers onsuch cellulose crepe wadding are relatively short and non-elastic andthus difficult to transfer through to another surface in great numbers.

A polyurethane (non-absorbent) and cellulose crepe wadding samplingcontaining no openings for filament transference exhibited an absorbencylevel from 2 to 3 percent less than the sample VI sampling above. It isalso of note that where a sampling of percent rayon [3 denier 1 9/16fiber length] was combined in a 20 percent polyurethane 96 inch sheetnonabsorbent] there was a 5 percent increment in absorbency whereopenings and filament transference was effected by barbed needles of thetype indicated in the examples.

Material Transference Employed Method Results 15% cheese cloth Barbedneedles, Syngyna absorbency 100% cotton; triangular shank of 9.30 gramscellulose crepe 15 gauge (0.072 wadding 10 lb. wgt. inch diameter) per3,000 sq. feet 800 needle holes (10 plies) per square inch 9 barbs perneedle A sampling of cheese cloth cellulose crepe wadding similar toexample VII above not subjected to needle punching exhibited 25 percentless absorbency than the sample VII material.

As may be noted from the above, not only is there increased absorbency(Samples I,III,IV,V) but materials heretofore not generally employed inthe manufacture of absorbent material, especially as a constituentmaterial, for a rather inexpensive item such as a tampon (Sample VII)can be made to reach acceptable absorbency levels for use in suchproducts.

It has also been found that it is possible to increase the absorbency ofan all rayon tampon. Where the constituents are layers weighing 2.2grams of rayon, it has been found that the needle punching operation(i.e., 800 strokes p.s.i. using a 15 gauge 0.072 diameter needle)spreads the filaments and realigns the filament orientation with aresultant increase in absorbency levels.

While all of the tests above were conducted employed 800 openings persquare inch, tests were conducted at varying levels from 10 openings persquare inch to over 1,000 openings per square inch, it being found thaton the materials tested a range of between 600-850 punches per squareinch gave best results.

In addition, increased absorbency occurs both in instances where theconstituent materials are the same and to a much greater degree wherethe constituent materials are dissimilar. Similarly while positiveresults have been obtained employing absorbent and non-absorbentcombinations, enhanced results occur where all of the constituentmaterials are absorbent. All that is required however, is that at leastone of the layers be absorbent and at least one of the layers containfilaments having a length sufficient to be eflectively transferredthrough the openings in one of the constituent materials, at least to asufficient degree to retain the integrity of the openings.

Hence, the absorbency levels of the absorbent composite is a functionof:

a. the constituent materials b. the size of the openings c. the numberof openings,

d. the number of filaments transferred e. the denier of filaments, and

f. specific gravity (density) of filaments By selectively varying any ofthe above such as by increasing the needle size, and/or the number ofbarbs per needle, or increasing the number of openings, or by otherwiseaffecting any of the above variables, selective grading of absorbencylevels can be accomplished.

The only major limiting factor (aside from raw material cost) wouldappear to be the ability of the constituents to withstand the needlepunching filament transference operation. As such, it is desirable thatthe transferee layer be of a material which will act well as a matrix toretain openings having filaments extending therethrough.

While the present invention has been described with particularity interms of its application to a tampon various other uses are possible. Itis to be further appreciated that the terms and expressions which havebeen employed are used for purposes of illustration, it is recognizedthough that various modifications are possible within the scope of theinvention as claimed.

Having thus described certain forms of the invention in some detail,what is claimed is:

1. A tampon comprising at least two constituent absorbent layers, one ofsaid layers having absorbent filaments, the other of said absorbentlayers having plurality of openings therethrough; a portion of saidabsorbent filaments extending through the openings in said other layerto form an integrated absorbent composite; said absorbent compositeoriented in said tampon whereby the major portion of said openingshaving filaments extending therethrough extend in a direction transverseto the body of said tampon.

2. A tampon comprising, a first strip of an absorbent composite, asecond strip of an absorbent composite, each of said strips includingsuperimposed layers of absorbent rayon and absorbent crepe paper; saidrayon layer having a plurality of filaments; said crepe paper having aplurality of openings; said rayon and paper layers united such that aportion of the filaments of said rayon layer extend through the openingsin said paper layers to form an integrated composite; said first andsecond strips of absorbent composite in superimposed relationship andformed into a substantially cylindrical compressed body such that themajor portion of said opening in said paper layers extend in a directiontransverse to said cylindrical body.

3. The tampon as claimed in claim 2 wherein the beofo in ho saidaerlaersisin ii ord er of to l d os peni ngs pee sguare inch and each ofsaid openings has a diameter of at least 0.072 of an inch.

2. A tampon comprising, a first strip of an absorbent composite, asecond strip of an absorbent composite, each of said strips includingsuperimposed layers of absorbent rayon and absorbent crepe paper; saidrayon layer having a plurality of filaments; said crepe paper having aplurality of openings; said rayon and paper layers united such that aportion of the filaments of said rayon layer extend through the openingsin said paper layers to form an integrated composite; said first andsecond strips of absorbent composite in superimposed relationship andformed into a substantially cylindrical compressed body such that themajor portion of said opening in said paper layers extend in a directiontransverse to said cylindrical body.
 3. The tampon as claimed in claim 2wherein the number of openings in each of said paper layers is in theorder of 100 to 1,000 openings per square inch and each of said openingshas a diameter of at least 0.072 of an inch.